1. Field of the Invention
The present invention relates to a stop control system for an engine.
2. Related Art
There has been conventionally known idle stop (idling stop) control in which an engine is stopped when predetermined engine stop conditions are satisfied after a vehicle is temporarily stopped at a traffic light or the like, and the engine is restarted in response to a throttle operation to restart the vehicle.
In the idle stop control, it is preferred to arrange a crankshaft at a predetermined crank angle so as to improve startability of the engine in restarting the engine at a time of being stopped.
Thus, a conventional engine start control device executes “rewind control” in which a motor is driven “after stop” of an engine to reversely rotate a crankshaft to a predetermined crank angle as disclosed in, for example,    Patent Document 1 (Japanese Patent Laid-Open Publication No. 2011-21588).
It is required for the conventional engine start control device to be provided with a motor, which can reversely rotate the crankshaft so as to execute the “rewind control” in which the crankshaft that has been stopped is reversely rotated.
When a starter motor is used as the motor for reversely rotating the crankshaft, a circuit that reversely rotates the starter motor is additionally required. When the motor for reversely rotating the crankshaft is provided separately from the starter motor, the number of motors itself increases, and the number of parts connecting the motor and the crankshaft also increases.
In the idle stop control, in an occasion where it is not clear in what stroke the engine is stopped, i.e., in a compression stroke, a explosion stroke, an exhaust stroke, and an intake stroke the engine, it also becomes necessary to forwardly rotate the crankshaft in restarting the engine so as to identify the stroke, which takes much time to restart the engine.
Meanwhile, in the idle stop control, in a case when the engine is stopped in different strokes each time, a time to restart the engine irregularly changes even when the stroke can be identified.